1. Field of the Invention
The present invention relates to so-called metal wood, especially to a hosel for connecting a shaft thereto.
2. Description of Prior Art
In recent years, for improvement of a sense of stability in hitting balls, a golf club head with a larger volume has been desired. According to prior art, however, as a distal end of a shaft penetrating through a hosel is connected to a sole, a length of a shaft within a head body is elongated, thereby increasing an entire weight of a golf club head, resulting in decreasing a volume of a head body which must be manufactured within a regular value of an entire weight. To eliminate such problem, for example, Japanese Utility Model Publication No. 63-17491 discloses a hosel formed by folding metallic crust and a shaft to be inserted thereinto which is positioned at a distance off above a sole. However, such prior art has a problem that a connection strength of a shaft to a head body is comparatively weak or low.
Further, there is also proposed another prior art for improvement of a connection strength of a shaft, which is explained with reference to FIGS. 9 to 11, wherein a reference numeral 31 is a metallic and hollow golf club head consisting of a main body member 32, a face member 33, an upper crust member 34 and a hosel member 35. These members 32 to 35 are made of titanium alloy respectively, being welded to one another. The main body member 32 forms a sole 36, a heel 37, toe 38 and a back 39 of a golf club head 31, constructing a container-shaped head body 31a together with the face member 33. The upper crust member 34 is tabular and secured onto the head body 31a, covering the same. The upper crust member 34 has a cut-out portion 40 at its heel 37 side. The hosel member 35 is formed cylindrical, while a flange 41 formed at a distal end thereof is welded to a sole 36 at its heel 37 side. An intermediate portion of the hosel member 35 is welded to the ends of the upper crust member 34, the face member 33 and the main body member 32 respectively.
In welding the above members, a cladding 42 is formed by certain filler material so that an upper surface of the upper crust member 34, an outer side-peripheral surface of the face member 33 and the main body member 32 and an upper peripheral surface of the hosel member 35 can form gently-curved continuous surface. Thereafter, to the hosel member 35 is connected a shaft 43.
However, according to the prior art, as an intermediate part of the cylindrical hosel member 35 is allowed to pass through the cut-out portion 40 of the upper crust member 34 in order to be welded to the upper crust member 34, the face member 33 and the main body member 32 respectively, the connection strength of the hosel member 35 to these members 32 to 34 has been comparatively low. Further, to improve the connection strength and finish its appearance, it would be necessary to form the cladding 42 for forming the gently-curved continuous surface extending from the upper surface of the upper crust member 34 up to the upper portion of the outer peripheral surface of the hosel member 35, thus necessitating much cladding in welding. Consequently, such prior art has further resulted in low productivity.